Automatic grain-scales



(N0 Model.)

J. H. FORSYTH. AUTOMATIC GRAIN SCALES.

Patented Oct 28, 1890.

JcwcrGC on #0 5 %wifmcsscs UNITED STATES PATENT OFFICE.

JOl'll H. FORSYTH, OF FARGO, NORTH DAKOTA.

AUTOMATIC GRAIN-SCALES.

SPECIFICATION forming part of Letters Patent No. 439,135, dated October 28, 1890. Application filed May 3, 1890. Serial No. 350,427. (No model.)

To aZZ whom, it may concern:

Be it known that I, JOHN H. FORSYTH, a citi- Zen of the United States, residing at Fargo, in the county of Cass and State of North Dakota, have invented certain new and useful Improvements in Automatic Grain-Scales, of which the following is a specification.

My invention is in the nature of an improvement upon an automatic grain-scale for which Letters Patent No. AO5,72S were granted me June 25, 1889, and refers more particularly to an improvement in a detent for that class of scales in which the grain passes through an oscillating weighing receptacle constructed with with two oppositely-arranged compartments which alternately receive and discharge the grain, the operation being actuated by the weight of the grain only, the objects of said improvements being to reduce the detent strain or pressure, to combine gravitypawls with a device for insuring their positive action, to provide said pawls witha delicate adjustment, and to arrange their stops so as to reduce the downward action necessary for their release; and I attain these objects by means of the devices hereinafter described in connection with the accompanying drawings, in which similar letters refer to similar parts.

Figure 1 in the drawings is a front view of the scale as attached to the head of an elevator E, which answers the purpose of a frame. Fig. 2 is a side view of same, and Fig. 3 avertical section of the weighing-box and elevator-head.

The forked hanger-arms B 13, connected at their fork ends by the rods L L, and having the weighing-box A pivoted therein at D, are suspended from the fork ends of a scale-beam O which straddles the head of the elevator, and is fulcrumed thereon on either side at e e, the scale being provided with two weights, one on each fork of the beam. The weighingbox A is divided into two compartments by the partition P, the center of the box being in vertical line with the center of the discharge-spout N of the elevator. Each compartment is provided with a receiving-port R at the top and a discharge-port O at the bottom, and below the box are two swinging plates or port-covers F F, the outer edges of said covers beinghinged orloosely suspended from the lower extremities of the hangerarms or the rods connecting the same, and the inner edges connected by suspending links d d to the weighing-box, said links being hinged or pivoted to the covers and also to the weighing-box, and arranged and adjusted to operate the swinging covers simultaneously with the oscillating of the box, so that when either compartment is in position to receive the grain the port-cover of that compartment is held snugly against the port until the load is ready to discharge, when it drops concurrently with the oscillating movement of the box.

K is an arm projecting upwardly from the weighing-box in a line from the oscillating center, and having pivoted atits outward extremity a detent-roller S and below said roller S in direct line between it and the oscillating center a deflecting-roller I.

T T are gravity-pawls pivoted to the hangerarms with their free ends adjusted to meet and engage the said roller S, said pawls being constructed with a stop-arm or elbow Z and with a recess a in the shoulder of the free end and provided with an adjustingscrew 1').

M is a horizontal track projecting from the frame and presenting an under surface to the impingement of the deflecting-roller I, andX X are stop-brackets also projecting from the frame to engage and trip the pawls T T.

The friction attending the release of detentlatches has heretofore been a source of serious inaccuracy in automatic weighing, as any variation, however slight, when many times repeated becomes serious in the aggregate, and therefore any avoidance of friction at this point, though apparently trifling, becomes a matter of great importance. It will be readily perceived that by extending the detentpoint fromthe center and beyond the limit of the box proper a leverage is gained to resist the oscillating tendency, and consequently the detent strain and friction therefrom are relieved in proportion as the detent-point is so extended.

The track M is intended to cover the entire travel of the roller 1, the roller not escaping beyond the ends nor any portion thereof rising above the under surface of track, its province being simply to deflect the roller 1 to one side or the other, carrying the roller S into position to be caught by the pawl T.

The pawls T T are provided with the arm or elbow Z, projecting from near the pivot end in order to admit of the stops X X being lo-' cat-ed between the pivot and the free end of the pawl instead of outside the latch, as usually arranged, by which arrangement less downward movement of the scale is required I to trip the pawl, thereby making the release more nearly instantaneous. The said pawls I are also provided withaset-screw b in the lip of the free end, the point of said screw being I intended to rest upon the roller S, by means of which the depth of latch may be readily and delicately adjusted.

In operation, the box A being tilted to bring either port opposite the discharge-spout of the elevator, it is held in that position by the pawl T engaging the roller S, as shown in Fig. 1, until sufiicient grain has runin to overbalance the scale-beam, when the box, with hangers and pawls,descends untilthe arm Zstrikes the stop X, which releases the pawl from engagement with the roller, and the preponderance of weight in that compartment causes the box to oscillate, opening the dischargeport of that compartment and transferring the flow of grain from the elevator into the opposite compartment. The outflowquicklyrelieving the overbala-nce of the scale-beam, the box again ascends and the roller S is caught by the opposite pawl, and so the operation is repeated. v

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is-

1. In an automatic scale, an oscillating weighing-box suspended from a scale-beam and provided with oppositely-arranged compartmen ts intended to alternately receive and discharge the grain and also pro 7ided with a projecting arm, said arm having two rollers pivoted thereto, one above the other,inaline from the oscillating center of the box,in combination with a track on the frame to deflect the lower roller and covering the entire travel of same, and gravity-pawls on the hangerarms to engage the top roller, substantially as described.

2. In an automatic scale, a double compartment, oscillating Weighing-box pivoted in hangers suspended from a scale-beam, a projecting arm on said box carrying two rollers, located one above the other on a line from the oscillating center, gravity-pawls pivoted to the hangers, and set-screws in the lips of said pawls to regulate the depth of lateh,suhstantially as described.

JOHN H. FORSYTII, 

